Glossary /
Custom Metric
Efficiency & cost
Custom Metric
Calculated KPIs that reflect your business, applied the same way across every channel.
Attribution & Measurement
Unit Economics
Data Governance & Nomenclature
Creative & Delivery
Audiences & Targeting
Mobile & Privacy
A custom metric is a calculated or derived measure built on top of raw platform metrics—such as contribution margin, blended CPA, or a custom efficiency ratio. It encodes your business logic once and applies it consistently across channels.
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What is Custom Metric?
Platforms hand you raw numbers: spend, clicks, conversions, conversion value. But the metrics you actually steer on—contribution margin, blended CPA, ROAS net of fees, payback ratios—are calculations layered on top of those raw inputs. A custom metric is where that calculation lives. The value is consistency. If three analysts each compute "blended CPA" in their own spreadsheet, you get three slightly different numbers. Defining the metric once—as a formula referencing standardized inputs—means everyone reports the same figure, computed the same way, on every channel. Good custom metrics also travel across platforms. "Cost per acquisition" only means something blended if the spend and the conversions underneath it are normalized first. A custom metric sits on top of that normalized base, so a single CPA or margin figure can span Google, Meta, and TikTok rather than living trapped inside one platform's reporting.
How Custom Metric differs across ad platforms
Google Ads
Google reports its own conversion and value columns under its own attribution and naming. A margin or blended-CPA metric you build there can't see Meta or TikTok spend—and Google's metric names won't match the other platforms' equivalents.
Meta
Meta names and counts conversions differently (e.g., its own purchase and value fields under its attribution windows). A custom metric defined inside Meta is locked to Meta's definitions—so a CPA there isn't directly comparable to a CPA built in Google Ads.
TikTok
TikTok adds a third set of metric names and counting rules. Building the same efficiency ratio three times, once per platform, guarantees three subtly different definitions—the core reason blended metrics need a normalized base before any calculation.
Common Custom Metric misconceptions
A custom metric is the same as a custom column inside the ad platform.
A platform custom column only references that platform's own data and definitions. A true custom metric sits on a normalized, cross-channel base, so the same formula produces a blended number that spans Google, Meta, and TikTok.
Custom metrics are just for vanity KPIs.
Custom metrics are how you encode the numbers you actually make decisions on—contribution margin, payback, net ROAS. Defining them once removes the spreadsheet drift where the same KPI means different things to different people.
Related Terms
Frequently Asked Questions
What is Custom Metric in simple terms?
A custom metric is a number you calculate yourself from the raw data the platforms give you—like profit margin or blended cost per acquisition. Instead of using only the platform's built-in metrics, you define your own formula and use it everywhere.
How does Custom Metric work?
Why does Custom Metric differ across ad platforms?
How does Clarisights report on Custom Metric?
Attribution & Measurement
Unit Economics
Data Governance & Nomenclature
Creative & Delivery
Audiences & Targeting
Mobile & Privacy
A custom metric is a calculated or derived measure built on top of raw platform metrics—such as contribution margin, blended CPA, or a custom efficiency ratio. It encodes your business logic once and applies it consistently across channels.
?
?
What is Custom Metric?
Platforms hand you raw numbers: spend, clicks, conversions, conversion value. But the metrics you actually steer on—contribution margin, blended CPA, ROAS net of fees, payback ratios—are calculations layered on top of those raw inputs. A custom metric is where that calculation lives. The value is consistency. If three analysts each compute "blended CPA" in their own spreadsheet, you get three slightly different numbers. Defining the metric once—as a formula referencing standardized inputs—means everyone reports the same figure, computed the same way, on every channel. Good custom metrics also travel across platforms. "Cost per acquisition" only means something blended if the spend and the conversions underneath it are normalized first. A custom metric sits on top of that normalized base, so a single CPA or margin figure can span Google, Meta, and TikTok rather than living trapped inside one platform's reporting.
How Custom Metric differs across ad platforms
Google Ads
Google reports its own conversion and value columns under its own attribution and naming. A margin or blended-CPA metric you build there can't see Meta or TikTok spend—and Google's metric names won't match the other platforms' equivalents.
Meta
Meta names and counts conversions differently (e.g., its own purchase and value fields under its attribution windows). A custom metric defined inside Meta is locked to Meta's definitions—so a CPA there isn't directly comparable to a CPA built in Google Ads.
TikTok
TikTok adds a third set of metric names and counting rules. Building the same efficiency ratio three times, once per platform, guarantees three subtly different definitions—the core reason blended metrics need a normalized base before any calculation.
Common Custom Metric misconceptions
A custom metric is the same as a custom column inside the ad platform.
A platform custom column only references that platform's own data and definitions. A true custom metric sits on a normalized, cross-channel base, so the same formula produces a blended number that spans Google, Meta, and TikTok.
Custom metrics are just for vanity KPIs.
Custom metrics are how you encode the numbers you actually make decisions on—contribution margin, payback, net ROAS. Defining them once removes the spreadsheet drift where the same KPI means different things to different people.
Frequently Asked Questions
What is Custom Metric in simple terms?
A custom metric is a number you calculate yourself from the raw data the platforms give you—like profit margin or blended cost per acquisition. Instead of using only the platform's built-in metrics, you define your own formula and use it everywhere.
How does Custom Metric work?
Why does Custom Metric differ across ad platforms?
How does Clarisights report on Custom Metric?
See Viewable Impression across every channel in one report
See Viewable Impression across every channel in one report
See viewability and vCPM across every platform—display, video, programmatic— in one normalized report, instead of reconciling vendor numbers by hand.
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